For example, WO 2015/136875 (Patent Document 1) describes that in a case where VLANs (Virtual Local Area Networks) are used for separation into a large number of logical networks in a large-scale mobile network to which server virtualization is introduced, the network is separated in units of VNI/VNID (VXLAN Network Identifier (hereinafter referred to as “VNID”), 24 bits) by applying VXLAN (Virtual eXtensible Local Area Network) as a countermeasure against the shortage of VLAN-IDs (12 bits).